Hyperfrontality in patients with schizophrenia during saccade and antisaccade tasks: a study with fMRI.

Aims: Antisaccadic eye movements, requiring inhibition of a saccade toward a briefly appearing peripheral target, are known to be impaired in schizophrenia. Previous neuroimaging studies have indicated that patients with schizophrenia show diminished activations in the frontal cortex and basal ganglia. These studies used target fixation as a baseline condition.

Functional MRI mapping of brain activation during visually guided saccades and antisaccades: cortical and subcortical networks.

Antisaccade tasks require a subject to inhibit a saccade toward a briefly appearing peripheral target and instead to immediately generate a saccade to an equivalent point in the opposite hemifield. Using functional magnetic resonance imaging (fMRI), we investigated the neural networks required to inhibit reflexive saccades and to voluntarily generate saccades. The results demonstrated that saccade and antisaccade tasks often bilaterally activate frontal, parietal and supplementary eye fields, lenticular nuclei and occipital cortex.

Determining vulnerability to schizophrenia in methamphetamine psychosis using exploratory eye movements.

Patients with methamphetamine (MAP) psychosis whose psychotic symptoms continued after MAP withdrawal were observed at Saitama Prefecture Government Psychiatric Hospital. The purpose of the present study was to ascertain whether some of these MAP psychosis subjects have a vulnerability to schizophrenia. Forty-eight patients with MAP psychosis were divided into three groups based on clinical course: transient type, prolonged type and persistent type.

Influence of arousal level for functional magnetic resonance imaging (fMRI) study: simultaneous recording of fMRI and electroencephalogram.

Simultaneous recording of functional MRI (fMRI) and electroencephalogram (EEG) has been applied to several clinical fields, making it possible to monitor the arousal level of the subject during a cognitive task. The study confirmed that activated cerebral areas were different between high and low arousal levels during the smooth-pursuit eye movement task. When arousal level was high, activations in the parietal eye field, frontal eye field (FEF), supplementary eye field (SMA), visual fields (V1) and occipito-temporal junction (V5) were found.